diff --git a/src/pyj/popups.pyj b/src/pyj/popups.pyj
index c63610130d..2e004b079a 100644
--- a/src/pyj/popups.pyj
+++ b/src/pyj/popups.pyj
@@ -106,4 +106,5 @@ class CompletionPopup:
         cs.top = 'auto' if upwards else y + 'px'
         cs.bottom = y + 'px' if upwards else 'auto'
         cs.width = width + 'px'
+        cs.maxHeight = ((y if upwards else window.innerHeight - y) - 10) + 'px'
         show_popup(self.container_id, *self.associated_widget_ids)